SFP transceiver modules almost always require two fiber optic cable strands. It offers significantly higher bandwidth, longer transmission distances, and greater resistance to electromagnetic interference than traditional copper cables. The optical ports on the switch are usually paired together, with one TX sender and one RX receiver. The. Answer first: a breakout works only when the parent port, switch ASIC or line card, software, lane map, child speeds, FEC, cable or optics, and all endpoints support the same channelization. A matching QSFP or OSFP shell alone is insufficient.